(a) Field of Disclosure
A thin film transistor array panel and a manufacturing method thereof are provided.
(b) Description of Related Technology
In general, a flat panel display such as a liquid crystal display (LCD), an organic light emitting diode display (OLED display), and an electrophoretic display includes a pair of opposed field generating electrodes and one or more electro-optical active layers that are interposed therebetween. The LCD includes a liquid crystal layer as the electro-optical active layer, while the OLED display includes an organic light emitting layer as the electro-optical active layer. One of field generating electrodes of a given opposed pair is generally connected to an electronically controlled switching element to thereby selectively receive an image defining electrical signal when addressed. The electro-optical active layer converts the received electrical signal into an optical signal, thereby causing display of a desired image portion.
The flat panel display may include a display panel having a plurality of thin film transistors (TFTs) integrally formed thereon. This panel is often referred to as the TFT array panel. Typically, the thin film transistor (TFT) array panel is patterned via photolithography during mass production to have multiple electrodes and semiconductive regions of various kinds. A plurality of masks and corresponding patterning processes are generally used in the mass production manufacturing process.
On the other hand, the semiconductive material used to form each TFT is an important factor in determining the operating characteristics of the TFT array. The commonly used semiconductive material is made of amorphous silicon. However, a disadvantage of amorphous silicon (Si-(a)) is that the charge mobility thereof is relatively low (as compared for example to that of single crystalline or polycrystalline silicon (Si-(p/a)). To alleviate this shortcoming, recently, mass production fabrication of thin film transistors using a semiconductive oxide and having relatively high charge mobility and a relatively high ON/OFF ratio of conducted current (Ion/Ileakage)—as compared with the conventional amorphous silicon transistor—has been researched.
The above information disclosed in this Background section is only for enhancement of understanding of the here disclosed technology and therefore it may contain information that does not form the prior art that is already known to persons of ordinary skill in the pertinent art.